Saturday, February 23, 2008

Self-Repairing Rubber

This is truly astounding! Just imagine the applications for a material which self-heals itself...and this is just the start...If these Scientists manage to refine and increase the repairing abilities, and apply it to metals and other materials, we're in for one crazy future! No more repairs required! No more car right-offs! And of course..robots with self-healing rubber "skin" and hardware!

Check out the original post below(and click on the bbc link to watcha video if you have real time player):

A material that is able to self-repair even when it is sliced in two has been invented by French researchers.

The as-yet-unnamed material - a form of artificial rubber - is made from vegetable oil and a component of urine.

The substance, described in the journal Nature, produces surfaces when cut that retain a strong chemical attraction to each other.

Pieces of the material join together again as if never parted without the need for glue or a special treatment.

This remarkable property comes from careful engineering of the molecules in the material.

The French researchers are already making kilogramme quantities in their Paris laboratories and say the process is almost completely green, and could be completely so with a few adjustments.

'Tiny hands'

The secret of the substance lies in how the molecules are held together.

A piece of normal rubber, says Dr Ludwik Leibler, who headed the research, is actually a single molecule with billion upon billions of smaller units chemically welded together to form a giant tangled network.

Children are always breaking their toys. Wouldn't it be nice if you could put them back together so easily? Ludwik LeiblerThe elasticity comes from the fact that the strands within the network are buckled like a concertina: pull on them and they straighten and elongate; let go and the buckles reappear.

But break a rubber (or most other solids), and the chemical welds - known as covalent bonds - are also broken.

These cannot be remade. Nor can a piece of rubber be remoulded or reshaped.

"We wanted to see if we could make a rubber-like material using small molecules," Dr Leibler of the Industrial Physics and Chemistry Higher Educational Institution (ESPCI) in Paris told the BBC's Science In Action programme.

The trick was to replace the covalent bonds in rubber with weaker connections known as hydrogen bonds.

These are like hands on neighbouring molecules that can clasp together, but let go when broken.

Dr Leibler quickly realised that this meant not only that the new rubber could be recycled and remoulded many times over, but that if separated by a cut or break, the chemical hands at the fresh surfaces would still be waving about ready to bind again.